Limestone contactors in containers
The DrinTec™ design of upflow limestone contactors of constant height simplifies the reload operation by means of feeding the granulated limestone continuously, under water and directly on to the limestone bed by using a limestone feeding system, thus maintaining a constant bed height all the time. It‘s a very effective system that will operate continuously for many years without needing to perform a backwash.
DrinTec™limestone Contactors of constant height in containerised horizontal tanks feature limestone feeding system, internal perimeter spillways, underdrain system for water and air and built-in calcite silo. Each unit is made according to project specific needs.
The designs allow for a guaranteed autonomy of more than 30 days and minimal wasted water if the outlet turbidity is properly controlled. This procedure has the advantage that the quality of the outlet water is always constant. Consequently, the operation and maintenance costs are reduced considerably over the traditional designs.
The limestone contactors are usually placed in parallel. Because they have the same height they offer the same counter-pressure. This facilitates the hydraulic design of the inlet manifold and provides an uniform and constant water distribution to the different tanks.
The limestone contactors operate by gravity with a low pressure drop, so they can operate directly with the outlet pressure of the reverse osmosis racks.
The turbidity is controlled using dust free material and maintaining a constant flow rate, i.e. avoiding sudden changes in flowrate. If the current flow is going to be increased, flow is initially diverted and incorporated gradually thereafter to the contactor.
There is very little need to purge the limestone contactors, as they operate upflow and do not tend to clog. However, at least once a year a 5 minutes sponging is recommended to reduce the risk of formation of preferential pathways.
Internal parts and the DrinTec™ process are protected by various patents.
Brochures
Advantages of DrinTec™ limestone contactor process:
- Designed for quick deployment
- Equipment shipped in standard ocean container
- Very high efficiency
- Flexible automation: fully, partial, none
- Constant performance and water quality
- Low maintenance cost
- Minimum or no energy consumption
- No moving parts
- More than 30 days autonomy
- No need for qualified workforce to operate
- No need for frequent backwash: At start up and then once a year
Technical Specs:
| 20′ container | 40′ container | Units | |
|---|---|---|---|
| Maximum treatable flow | Up to 1100* | Up to 2800* | m³/d |
| Turbidity | < 1 | NTU** | |
| Container weight (empty tank) | ≈3000 | ≈7500 | kg |
| Container weight (full tank) | ≈35000 | ≈75000 | kg |
| Maximum inlet pressure | 1 | bar | |
| Outlet pressure | Atmospheric | ||
| System autonomy | >30 | days | |
| “Worm Tank” dimensions | 4790 x 1625 x 2000 | 4790 x 1625 x 2000 or 4790 x 1625 x 2250 |
(l x w x h) mm |
| Container type | 20’ Standard | 40’ High Cube | |
| Container internal dimensions | 5900 x 2350 x 2393 | 12036 x 2350 x 2693 | (l x w x h) mm |
| Design temperature | 40 | ºC | |
| Required material for operation | Granulated calcite & CO2 | ||
| Energy consumption | Nil | KWh/m³ | |
| Installation | “Plug and play” | ||
| Time between backwashing | At start up and then once a year | ||
| Backwash water | 220 | 220 | m3/h at 1 bar |
| Backwash air | 500 | 500 | Nm3/h at 0,7 bar |
* Depends on permeate characteristics and water temperature.
** Assuming that the calcite quality is according to the recommendations in our technical brochure.
